Valve mechanism



Jan. 19, 1943. R c, TEMPLE 2,308,727

VALVE MECHANISM Filed June 11, 1941 2 Sheets-Sheet 2 ,I/ as 93 89 79 W rA PA UL C. TEMPL E Patented Jan. 19, 1943 VALVE MECHANISM Paul Temple,Decatur, 111., assignor to A. W. Cash Company, Decatur, 111., acorporation of Delaware Application June 11, 1941, Serial No. 397,569

9 Claims.

This invention relates to valve mechanisms, and more particularly tovalves adapted to control the operation of hydraulic motors.

Tractors are frequently provided with imple-. ments .such as graders,scrapers, bulldozers, or snow plows which can be raised and lowered bymeans of hydraulic motors supplied with oil or other fluid underpressure from a suitable source. Such motors'are controlled by manuallyactuated valves. In some cases two such implements may be mounted on thesame tractor. For example, a tractor may have a bulldozer on itsfront-end and a scraper on its rear end, with an independently operablecontrol valve for each. It is of course desirable to supply both thesecontrol valves with fluid from a common pump. However, if one of thevalves is in its neutral position, allowing free circulation of thefluid at low pressure, there will be no fluid available at the higherpressure necessary for operation of the motor corresponding to the othercontrol valve. Consequently the system would become inoperative underthese conditions. Furthermore, it has been the practice to employ aseparate casing for each of these control valves, and since each casingmusthave several connections for the flow of oil, the piping required isbulky and expensive.

It is accordingly one object of the invention to. combine with a pair01' independently controlled valves a simple and dependable automaticmeans for directing all the fluid from a common source to such of saidvalves as may require the same.

It is a further object of the invention-to provide a valve'mechanism oicomparatively simple and dependable construction adapted to control theoperation or the hydraulic motors independently.

It is a further object 01 the invention to provide a dual valvemechanism having a single casing and so constructed and arranged as tosimpliiy the various piping connections required.

With these and other objects in view, as will be apparent to thoseskilled in the art, the invention resides in the combination of partsset forth in the specification and covered by the claims appendedhereto.

Referring to the drawings illustrating one embodiment oi the invention,and in which like reference numerals indicate like parts:

Fig. 1 is a'longitudinal section through a dual valve mechanism, thesection being taken on the line of Fig. 3;

I opening 2| (Fig. 5).

Fig. 2 is an elevation of the valve mechanism with other apparatusconnected thereto;

Fig. 3 is a section on the line 3-4 of Fig. 1;

Fig. 4 is a section on the line 44 of Fig. 1; and

Fig..5 is a section on the line 5-5 of Fig. 1.

The embodiment illustrated comprises a hollow casing III which is formedof flve separate parts for convenience in manufacture and assembly.These parts include a central body valve housings l2 and I4 mounted onopposite sides of the body, and heads l5 and I6 which close the outerends of the respective housings, all as shown in Fig. 1. An elongatedexhaust chamber I8 is provided in the upper portion or the casing, andan exhaust passage l9 extends uwardly from this chamber in the centralbody Directly beneath this passage l9 there is located an inlet chamber2|! having an inlet A port 23 leads from the inlet chamber to theexhaust chamber, and this port is normally closed by a pressure reliefvalve 24 which is loaded by means of a coiled compression spring 25. Theconstruction is such that the valve 24 will open if necessary to preventthe fluid pressure in the inlet chamber from exceeding a predeterminedvalue. As shown in Fig. 3, the housing I2 is shaped to provide twochambers 21 and 28 which, ior'lack of better terms, will be respectivelydesignated as "raise" and lower" chambers. Two openings 29 and 30communicate with these chambers respectively. As shown in Fig. 4, thehousing I4 is shaped to' provide a raise chamber 32 and a lower chamber33 with which two openings 34 and 35 communicate respectively.

Referring now to Fig. 2, it will be seen that V the central body II issecured directly to the bottom 01' a tank or reservoir 31. This tankcontains a suitable operating fluid. such as oil, and the exhaustopening I! is in direct-communication with the tank. The opening 29 isconnected by a pipe 38 to the lower end of an uprightcylinder-39, andthe opening 30 is connected by a pipe 4| to the upper end of this samecylinder.

' Within the cylinder there is provided a slldable piston 42 having apiston rod 43. The opening 34 is connected by a pipe 45 to the lower endof anupright'cyllnder', and the opening 35 is connected by a pipe 41 tothe upper end of this same cylinder. vided a slldable piston 49 having apiston rod ill. Oil is withdrawn from thetank 31 through a-pipe 5| bymeans of a pump 53 and delivered through a pipe 54 to the inlet opening2|. T e pump may be driven by any suitable source of power.

Withinthe cylinder there is pro.-'

The entire apparatus may be mounted upon a tractor, and the piston rod43 may be connected to a scraper on the rear end of the tractor, whilethe piston rod may be connected to a bulldozer on the front end of thetractor. Referring now to Figs. 1 and 3, it will be seen that thehousing I 2 is provided with a cylindrical bore to receive a rotaryvalve 57. -Theends of this valve are supported in two ball bearings 58mounted within the bore 56. A stem extends axially outward from one endof the valve and through the head l5, the outer end of this stem havinga handle 6| thereon, so that the control from a scraper. The valve andits associated housing ports are preferably construct ed in accordancewith the disclosure in my prior patent application Serial'No. 388,815 fldApril.

16, 1941. The ends of this valve are supported in two ball bearings Blmounted' within the bore 19. v

A stem 93 extends axially outward from one end oftthe valve and throughthe head l6 .;the outer endof this stem having a handle 84" thereon, soThe 7 that the valve may be turned about its axis.

central portion" of the valve is provided with a valvemay be turnedabout its axis; The cen-M tral portion of the valve is provided with adialmetrically extending port 92 which connects with an axial passage 63leading directly into the inlet chamber 20. Adjacent theends of the portings 58 the diameter is reduced; as shown in Fig. 1,.to allowcirculation of fluid around the reduced p i n -{M Several ports areprovided in thewall of the bore. 56. A port 65 connects the exhaustchamber I8 with the bore, and a port is located"diav metrically oppositethe port 651 There' ar also two ports 61 and which connect the chambers21 and 28 respectively with the bore, These last- I mentioned ports arelocated ninetydeg'rees apart,

' rand forty-Ifive degrees from the ports 59 and respectively. Alongitudinal port (gr groove 69 is providedflln the outer surface of'thevalve, this port being located ninety degrees from thedia metricallyextending port 62 and on thesame side as the ports 61 and 69. On theopposite side .of

the valvefrom the port there is provided a cam 11 having a notchtherein, this cam being ongaged by an indexing roller 13 carried by asmall 1 plunger 15. This plungeris slldably mounted'in a radiallyextending bore 16 in the housing 12.

Acoiled compression spring 11 urges the plunger inwardly, the parts.being so constructed and arranged that when the roller 13 rests inthe'notch 12, the valveiport 62 will be in registration with the housingexhaust, ports 65 and 56 as shown in Fig. 3,-the ports Gland "beingclosed. This'will hold the'piston l2 stationary." The portsiLfG'l and"are of substantially the same length, in a i direction parallel with theaxis of the valve, but

the ports 95, B5 and 69 are somewh'atlonger. Thus, when the valve isturned forty-five degrees in a clockwise direction from the positionillustrated, the valve port 62 will register with the housing port 68 toadmit fluid theret whe'reas the valve p0rtt69 will registerwith thehousing port 91 to exhaust fluid therefrom, and the piston 42 will belowered. Similarly, when the valve is turned forty-five degrees in ananti-clockwise ,dl-

rection from the position shown, the valve port 62 V will register withthe housing port 61 toadmit fluidthereto, and the valve port'69willregister with the housing port 69 to exhaust fluid there from. This willcause the piston 42 to move upwardly. The valve .51 thus providesa meansfor raising and lowering the scraper or other device connectedto thepiston rod 43, and for holdingthe same fixed in any desiredposition.

" Referring Figsland a whit seen that the housing M is-provlded with acylindrical bore "toreceive a rotary valve Olljwhichyis axially alignedwith the valve 51, ,While these a two valves may be of identicalconstruction, there are preferably certain differences for the reasonthat a bulldozer requires a somewhat different 62 the valve hassubstantially the same diameter as the bore 56, to form aseal, but nearthe beardiametrically extending: port which. connects withan axialpassage 86 leading directly into the inlet chamberlll; Adjacent the endsof the port 95 thevalve hassubstantially the same diameter as the bore19 to form a seal, but near the bearings 9| the diameter is reducedtoallow circula-,

tion of fluid around the reduced portions;

1 Several ports are provided in thewall ofthe bore-19. A port 88connects the exhaust chamber I8 with the bore, anda port is locatedvdiametrically opposite itheportll" There are also two diametricallyoppositapo'rts 90 and 9| which are circumferentially spacedapproximately sixty degrees from thefports 89 and 99-"respectively.

These four ports are elongated in thenaxialjjdi- V rectionsufilcientlyito ensure [that they will remaln g' in communicationaroundzthe' valve regardless of its position. Between the portsanally-there is provided a port 93 which leads directly to the lowerchamber 33; About-thirty degrees cir- 'cumferemzially from the-port 88;and on th opposite-side thereof from the port, there-ls provided a port94 which is 'connected'with the'flfraisef";

chamber 32 bymeansfiof apassager-li- These ports 93 and are shorter inthe; axial direction than the ports 89,99,10 and 9|, and preferably "ofsubstantially the same'siz e'as the valve port 85,

for reasons'which will bemade apparent hereinafter.

which overlapsand closestheport 93 when the valve port is alignedfwlth'the ports 98 and", The passage 95 has associatedtherewitha check valve98; of the poppet typearrang'ed to open in the direction of flow towardthe fraise' chamber Thisvalve is formedwitha cylindrical sleeve 99 whichis slidably supported in a plug I00 screwthreaded inthe housing I,anditcooperates with an annular seatzmember 102 mounted in the passage.The valve 7991s arranged to be .openedby 7 means of" a plunger I03aligned therewith and slidably mounted in the-housing lhoneend of thisplunger extending; into the bore 19in posi-' tion to be engaged by a camInformed on one side of therotary valveglll. This camis so shaped thatthe valve}! willnbe open ,whentherotary valve an is turned when; theport'ssiii o gi chamber 32. In order, to avoid this dimc'ulty, this I 65valve' is formed'with a passage I06 which extends v suandali t Since thecheckvalve 99'is unbalanced, considerableforce would berequired to" openit directly against a high fluid pressure in the.'raise tration eitherwith theiport 93 or with the ports axially therethrough, the 'flolwthrough this passage being controlledibyv a pilot check valve lll'lx;

arranged to open inthesame directionas the main valve 98Acolledicompressionfspring I99 urges the pilot valve I91 towarditsclosedposition. The pilotfvalve isprovided with 'a valve stem .l l fl,this stem being long enough" to licengaged by the plunger. 1 09 slightlybefore the latter engages the main valve 98; This stem Iljllj fisofnon-circular cross-section to avoid complete'clos- As shown inFlg. 4,the valve Bills formed with a 'circumferentlally, extended portion: 96 Yure of the passage I06. A small orifice III is provided in the sleeve 99to allow fluid from the chamber 32 to reach the pilot valve I01. Oncethe pilot valve is opened, fluid may flow through the orifice I I I andpassage I06 to reduce the unbalanced load on the main valve andfacilitate the opening thereof.

In order to assist the operator in adjusting the rotary valve 80 todesired positions, this valve is provided with an index cam H3 at theside opposite the cam I04. This index cam is engaged by a roller II4which is mounted on the inner end of a plunger II5, the latter beingslidable in a bore II1v formed in the housing I4 and extending radiallyinto the main bore 19. The plunger H5 is urged inwardly by means of acoiled compression spring H0. The cam H3 is provided with a recess H9 inwhich the roller rests when the valve 80 is in the neutral positionshown in Fig. 4, and with a recess I20 in which the roller rests whenthe valve is turned to its float position, with the port 85 inregistration with the ports 90 and SI. The recess H9 is considerablynearer the axis of the valve than the recess I20. Moreover, the camsurfaces at opposite sides of the recess 'I I9 are inclined inwardlytoward the same, so that the pressure of the roller will return thevalve to neutral position from either the raise position in which theport 85 registers with the port 94, or the flower position in which theport 85 registers with the port 93,4i 3on release of the handle 84. Oncethe valve is placed in its float position, it will be held there untilit is turned by means of the handle.

Thus it is in only the raise and lower positions that the operatorneedretain his grip on the handle. A projecting portion I2I of the camis so located as to engage the roller when the valve is in the lowerposition, to assist the operator, in placing the valve accurately inthis position. It will be apparent that with the valve in the neutralposition shown in Fig. 4, oil will circulate at low pressure from theinlet port 86 to the exhaust chamber I8, the port 93 being closed by thevalve portion 96, and the passage 95 being closed by the check valve 98,which will prevent any leakage of fluid despite relatively high oilpressure in the raise chamber 32 caused by the weight of the bulldozer.By turning the valve 80 to its raise position, oil will be admitted tothe port 94 and exhausted from the port 93, thus raising the bulldozer.By turning the valve to its lower position, 011 will be .admitted to theport 93 and exhausted from the port94, the check valve 96 being heldopen by the cam I04, so that the bulldozer will be lowered. With. thevalve 80 in its float position, the oil will circulate freely, both theports 93 and 94 will be open to the exhaust, and the check valve 98 willbe held open, so that the bulldozer may move up and down freely andfollow the contour of the ground. 7

It will be apparent from the above disclosure that the valves 51 and 60can be actuated independently to control their respective hydraulicmotors, but for this control to be .eflective it is necessary that oilbe available at a sufficiently high pressure to actuate the motors whenrequired. However, both valves receive their oil supply from the sameinlet chamber 20, and each valve is constructed to allow freecirculation of oil at low pressure except when the corresponding motoris being actuated. Consequently, with the construction as so fardescribed, it either valve is position by the springs in its neutralposition and the other valve is turned in an attempt to actuate itscorresponding motor, no pressure will be available for such actuation,since all the oil delivered by the pump will flow freely to the exhaustthrough the first valve. V

This difliculty is avoided by a mechanism which will now be described.Referring to Fig, 1, it will be seen that the adjacent inner ends of therotary valves 51 and 60 are spaced apart so that oil from theinletchamber 20 may enter the central valve ports 63 and 66. These adjacentinner ends are finished smoothly to provide annular valve seats, andbetween them there is mounted a disk-shaped valve I23. This valve isyieldably biased toward the central or neutral position shown in thedrawings, in which both the ports 63 and 86 are open, but it can movetoward either of the rotary valves to close the corresponding porttherein. For this purpose the valve I23 isv providedwith oppositelyextending axially aligned stems I24, the outer ends or these stemsresting slidably in recesses I25 formed in the inner ends of the rotaryvalve stems 60 and 83. Within each or these recesses there is mounted acomparatively light coiled compression spring I26.

The. operation of the invention will now be apparent from the abovedisclosure. So long as both the valves 51 and are in their neutralpositions, the oil entering the inlet chamber 20 from the pump 53 willdivide at the valve I23, half of the oil entering the valve port 63 andthe other half entering the valve port 86. From these valve ports theoil will flow freely and at low pressure to the exhaust chamber I8;Since the fluid pressures on the valve I23 are balanced, this valve willbe yieldably held in its central I26. If now the operator wishes toraise the scraper, he will turn the valve 51 by means of the handle 6Ito the raise position, with the valve port 62 in registration with theport 61. Any oil now entering the valve port 63 will be directed intothelower end of the cylinder 39, but such flow cannot occur withoutmoving the piston 42 which is connected to the scraper, and the pistonwill not raise the scraper so long as the oil pressure remains at a lowvalue. Consequently all the oil delivered by the pump will enter thevalve port 06 and there will be a drop in the pressure of the oil as itflows inwardly between the valve I23 and the inner end of the rotaryvalve 60, This will unbalance the fluid pressures on the valve I23 sothat it will move to the right in Fig. 1 and close the valve port 86,causing all the oil delivered by the pump to flow into the valve port 63and thence'to the cylinder 39. The pressure will immediately increase tothe value necessary to move the piston 42. When the rotary valve 51 isreturned to its neutral position, the unbalanced pressure on the valveI23 will be released and the springs I26 will retum-it to the centralposition shown in Fig. l. Similiarly it the rotary valve 60 is turned inorder to change the position or the bulldozer, flow through the valveport 86 will be momentarily It win also be noted that u the rotary valveso is placed in its float position the oil can circulate i'reelytherethrough at low pressure, just as in the neutral position, and thevalve II; will accordingly remain in its neutral position until one orthe other of the rotary valves is moved to a position suchjthat oil at ahigher pressure is required.

, It will now be apparent that the invention provides a comparativelysimple, inexpensive and dependable valve mechanism including twoindependently operabl valves. Both these valves are mounted in a. singlecasin and only one inlet opening and only one exhaust opening isrequired. Consequently the meohanism is more.

compact and fewer piping connections are need ed. The construction issuch that theoil is norindependently operable control valve: associatedwith each port, each valve having a neutral position in which the fluidentering the corresponding .port will be allowed to exhaust at lowpressure and an operating position in which the fluid will be directedto a place of use, and means operable automatically, when either of thevalves is ,moved to its operating position, to close the port associatedwith the other valve 2."A valve mechanism comprising two independentlyoperable control valves, common means to supply fluid under pressureitoboth valves, each valve having a neutral position in which the fluidwill be allowed to exhaust at low pressure and an operating position inwhichthe fluid willbedirected to a place oi use, and a valve deviceactuated by variations in the fluid pressure and arranged to preventflow oi fluid to one control valve in its neutral position when theother control valve is moved to its operating pomtion.

3. A valve mechanism comprising. a casing shaped to provide an inletchamber for fluid 'under pressure, two independently operable controlvalves arranged to receive fluid from the said chamber, each valvehaving a neutral position in which the fluid will be allowed to exhaustat low pressure and an operating position in which the fluid will bedirected to a place or use, and a valve device located in the inletchamber and arranged to prevent flow of fluid to one control valve inits neutral position when the other ,control valve is moved to itsoperating position.

directions from its centralposition and arranged 4. A valve mechanismcomprising a casing shaped to provide an inlet chamber for fluid unederpressure and an exhaust chamber, two independently operable controlvalves arranged to receive fluid from the inlet chamber, each valve 7having a neutral position in which the fluid will be directed into theexhaust chamber and an operating'position in which the fluid will bedirected to a place of use, and a valve device 10- position. 7. A valvemechanism comprising 'a casing shaped to provide an-inlet chamber forfluid under pressure with two ports leading outwardly therefrom, anindependently operable control valve associated with each port, eachvalve having a neutral position in which the fluid entering thecorresponding port will be allowed to exhaust at. .low pressure and anoperating position in which the fluid will be directed to a place ofuse. a valve device located in the inlet chamberto control the flow into.thesaid ports, the valve device having'a central position such thatfluid may enter both ports, and means yieldably biasing the valve devicetoward its central position,

the valve device being arranged to close one'oi" the ports when thecorresponding control valve is in its neutral position and theothercontrol valve is moved to itsoperatingposition.

6. A valve. mechanism comprising a casing shaped to provide an inletchamber for fluid under pressure with two opposed ports leadingoutwardly therefrom, an independently operable control valve associatedwith each port,=each valve having a neutral position in which the,

fluid entering the corresponding port will be allowed to exhaust at lowpressure and an oper: ating positionin which thefluid will be directedto a place'oi use, a valve device. mounted between the ports to controlthe flow into the same, the valve device having acentral position suchthat fluid may enter both ports, and means yieldably uoome valve devicebeing movable in opposlte to close one of the portswhen thecorresponding control valve is-in its neutral position and the othercontrol valve is moved to its operating under pressure with" two opposedand aligned ports leading outwardly therefrom, an independently operablecontrol valve associated with each port, each valvehaving a neutralposition-in whichthe fluid entering the corresponding port will beallowed to exhaust at low central position and arrangedto be movedbythe, fluid pressure and close one o! the ports when the correspondingcontrolvalve is-in its neutral is moved position a'nd the othercontrolvalve to its operating pomtion.

A valve mechanism comprising a casing shaped to provide an inlet chamberior fluid under'pre'ssure, two independently operable 1'0- tary controlvalves mo'unted on opposite sides 01' r. the inlet chamber and axiallyaligned, each valve having an axially located port communicating Y withthe inlet chamber and surrounded at its inner end by an annular valveseat, eachvalve cated in the inlet chamber and actuated by vahaving aneutral position in'whlch the fluid entering the corresponding.) portwill be allowed to exhaust at low pressure and an operating -position inwhich the fluid will be directed to a place of use, a valve devicereciprocally mounted between the valve seats to control the flow intopressure and. an operating position inwhich the fluid will be,

the ports, the valve having a central position such that fluid may enterboth ports, and means yieldably biasing the valve device toward itscentral position, the valve device being movable in opposite directionsfrom its central position and arranged to be moved by the fluid pressureinto contact with one of the valve seats when the corresponding controlvalve is in its neutral position and the other control valve is moved toits operating position.

9. A valve mechanism comprising a casing shaped to provide an inletchamber for fluid under pressure, two independently operable rotarycontrol valves mounted on opposite sides of the inlet chamber andaxially aligned, each valve having an axially located port communicatingwith the inlet chamber and surrounded at its inner end by an annularvalve seat, each valve having a neutral position in which the fluidentering the corresponding port will be allowed to exhaust at lowpressure and an operating position in which the fluid will be directedto a place of use, a disk-shaped valve device mounted between the valveseats and provided on opposite sides with valve stems which extend intothe said valve ports, means slidably supporting the valve stems, andsprings engaging the valve stems and yieldably biasing the valve deviceto a central position midway between the valve seats and such that fluidmay enter both ports, the valve device being arranged to be moved by thefluid pressure into contact with one of the valve seats when thecorresponding control valve is in its neutral position and the othervalve is moved to its operating position.

PAUL C. TEMPLE.

